drivers/input/keyboard/ep93xx_keypad.c

   1 /*
   2  * Driver for the Cirrus EP93xx matrix keypad controller.
   3  *
   4  * Copyright (c) 2008 H Hartley Sweeten <hsweeten@visionengravers.com>
   5  *
   6  * Based on the pxa27x matrix keypad controller by Rodolfo Giometti.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * NOTE:
  13  *
  14  * The 3-key reset is triggered by pressing the 3 keys in
  15  * Row 0, Columns 2, 4, and 7 at the same time.  This action can
  16  * be disabled by setting the EP93XX_KEYPAD_DISABLE_3_KEY flag.
  17  *
  18  * Normal operation for the matrix does not autorepeat the key press.
  19  * This action can be enabled by setting the EP93XX_KEYPAD_AUTOREPEAT
  20  * flag.
  21  */
  22
  23 #include <linux/platform_device.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/clk.h>
  26 #include <linux/io.h>
  27 #include <linux/input/matrix_keypad.h>
  28 #include <linux/slab.h>
  29
  30 #include <mach/hardware.h>
  31 #include <mach/ep93xx_keypad.h>
  32
  33 /*
  34  * Keypad Interface Register offsets
  35  */
  36 #define KEY_INIT                0x00    /* Key Scan Initialization register */
  37 #define KEY_DIAG                0x04    /* Key Scan Diagnostic register */
  38 #define KEY_REG                 0x08    /* Key Value Capture register */
  39
  40 /* Key Scan Initialization Register bit defines */
  41 #define KEY_INIT_DBNC_MASK      (0x00ff0000)
  42 #define KEY_INIT_DBNC_SHIFT     (16)
  43 #define KEY_INIT_DIS3KY         (1<<15)
  44 #define KEY_INIT_DIAG           (1<<14)
  45 #define KEY_INIT_BACK           (1<<13)
  46 #define KEY_INIT_T2             (1<<12)
  47 #define KEY_INIT_PRSCL_MASK     (0x000003ff)
  48 #define KEY_INIT_PRSCL_SHIFT    (0)
  49
  50 /* Key Scan Diagnostic Register bit defines */
  51 #define KEY_DIAG_MASK           (0x0000003f)
  52 #define KEY_DIAG_SHIFT          (0)
  53
  54 /* Key Value Capture Register bit defines */
  55 #define KEY_REG_K               (1<<15)
  56 #define KEY_REG_INT             (1<<14)
  57 #define KEY_REG_2KEYS           (1<<13)
  58 #define KEY_REG_1KEY            (1<<12)
  59 #define KEY_REG_KEY2_MASK       (0x00000fc0)
  60 #define KEY_REG_KEY2_SHIFT      (6)
  61 #define KEY_REG_KEY1_MASK       (0x0000003f)
  62 #define KEY_REG_KEY1_SHIFT      (0)
  63
  64 #define EP93XX_MATRIX_SIZE      (EP93XX_MATRIX_ROWS * EP93XX_MATRIX_COLS)
  65
  66 struct ep93xx_keypad {
  67         struct ep93xx_keypad_platform_data *pdata;
  68         struct input_dev *input_dev;
  69         struct clk *clk;
  70
  71         void __iomem *mmio_base;
  72
  73         unsigned short keycodes[EP93XX_MATRIX_SIZE];
  74
  75         int key1;
  76         int key2;
  77
  78         int irq;
  79
  80         bool enabled;
  81 };
  82
  83 static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
  84 {
  85         struct ep93xx_keypad *keypad = dev_id;
  86         struct input_dev *input_dev = keypad->input_dev;
  87         unsigned int status;
  88         int keycode, key1, key2;
  89
  90         status = __raw_readl(keypad->mmio_base + KEY_REG);
  91
  92         keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
  93         key1 = keypad->keycodes[keycode];
  94
  95         keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
  96         key2 = keypad->keycodes[keycode];
  97
  98         if (status & KEY_REG_2KEYS) {
  99                 if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
 100                         input_report_key(input_dev, keypad->key1, 0);
 101
 102                 if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
 103                         input_report_key(input_dev, keypad->key2, 0);
 104
 105                 input_report_key(input_dev, key1, 1);
 106                 input_report_key(input_dev, key2, 1);
 107
 108                 keypad->key1 = key1;
 109                 keypad->key2 = key2;
 110
 111         } else if (status & KEY_REG_1KEY) {
 112                 if (keypad->key1 && key1 != keypad->key1)
 113                         input_report_key(input_dev, keypad->key1, 0);
 114
 115                 if (keypad->key2 && key1 != keypad->key2)
 116                         input_report_key(input_dev, keypad->key2, 0);
 117
 118                 input_report_key(input_dev, key1, 1);
 119
 120                 keypad->key1 = key1;
 121                 keypad->key2 = 0;
 122
 123         } else {
 124                 input_report_key(input_dev, keypad->key1, 0);
 125                 input_report_key(input_dev, keypad->key2, 0);
 126
 127                 keypad->key1 = keypad->key2 = 0;
 128         }
 129         input_sync(input_dev);
 130
 131         return IRQ_HANDLED;
 132 }
 133
 134 static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
 135 {
 136         struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
 137         unsigned int val = 0;
 138
 139         if (pdata->flags & EP93XX_KEYPAD_KDIV)
 140                 clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV4);
 141         else
 142                 clk_set_rate(keypad->clk, EP93XX_KEYTCHCLK_DIV16);
 143
 144         if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
 145                 val |= KEY_INIT_DIS3KY;
 146         if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
 147                 val |= KEY_INIT_DIAG;
 148         if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
 149                 val |= KEY_INIT_BACK;
 150         if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
 151                 val |= KEY_INIT_T2;
 152
 153         val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
 154
 155         val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
 156
 157         __raw_writel(val, keypad->mmio_base + KEY_INIT);
 158 }
 159
 160 static int ep93xx_keypad_open(struct input_dev *pdev)
 161 {
 162         struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
 163
 164         if (!keypad->enabled) {
 165                 ep93xx_keypad_config(keypad);
 166                 clk_enable(keypad->clk);
 167                 keypad->enabled = true;
 168         }
 169
 170         return 0;
 171 }
 172
 173 static void ep93xx_keypad_close(struct input_dev *pdev)
 174 {
 175         struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
 176
 177         if (keypad->enabled) {
 178                 clk_disable(keypad->clk);
 179                 keypad->enabled = false;
 180         }
 181 }
 182
 183
 184 #ifdef CONFIG_PM
 185 /*
 186  * NOTE: I don't know if this is correct, or will work on the ep93xx.
 187  *
 188  * None of the existing ep93xx drivers have power management support.
 189  * But, this is basically what the pxa27x_keypad driver does.
 190  */
 191 static int ep93xx_keypad_suspend(struct platform_device *pdev,
 192                                  pm_message_t state)
 193 {
 194         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 195         struct input_dev *input_dev = keypad->input_dev;
 196
 197         mutex_lock(&input_dev->mutex);
 198
 199         if (keypad->enabled) {
 200                 clk_disable(keypad->clk);
 201                 keypad->enabled = false;
 202         }
 203
 204         mutex_unlock(&input_dev->mutex);
 205
 206         if (device_may_wakeup(&pdev->dev))
 207                 enable_irq_wake(keypad->irq);
 208
 209         return 0;
 210 }
 211
 212 static int ep93xx_keypad_resume(struct platform_device *pdev)
 213 {
 214         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 215         struct input_dev *input_dev = keypad->input_dev;
 216
 217         if (device_may_wakeup(&pdev->dev))
 218                 disable_irq_wake(keypad->irq);
 219
 220         mutex_lock(&input_dev->mutex);
 221
 222         if (input_dev->users) {
 223                 if (!keypad->enabled) {
 224                         ep93xx_keypad_config(keypad);
 225                         clk_enable(keypad->clk);
 226                         keypad->enabled = true;
 227                 }
 228         }
 229
 230         mutex_unlock(&input_dev->mutex);
 231
 232         return 0;
 233 }
 234 #else   /* !CONFIG_PM */
 235 #define ep93xx_keypad_suspend   NULL
 236 #define ep93xx_keypad_resume    NULL
 237 #endif  /* !CONFIG_PM */
 238
 239 static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
 240 {
 241         struct ep93xx_keypad *keypad;
 242         const struct matrix_keymap_data *keymap_data;
 243         struct input_dev *input_dev;
 244         struct resource *res;
 245         int err;
 246
 247         keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
 248         if (!keypad)
 249                 return -ENOMEM;
 250
 251         keypad->pdata = pdev->dev.platform_data;
 252         if (!keypad->pdata) {
 253                 err = -EINVAL;
 254                 goto failed_free;
 255         }
 256
 257         keymap_data = keypad->pdata->keymap_data;
 258         if (!keymap_data) {
 259                 err = -EINVAL;
 260                 goto failed_free;
 261         }
 262
 263         keypad->irq = platform_get_irq(pdev, 0);
 264         if (!keypad->irq) {
 265                 err = -ENXIO;
 266                 goto failed_free;
 267         }
 268
 269         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 270         if (!res) {
 271                 err = -ENXIO;
 272                 goto failed_free;
 273         }
 274
 275         res = request_mem_region(res->start, resource_size(res), pdev->name);
 276         if (!res) {
 277                 err = -EBUSY;
 278                 goto failed_free;
 279         }
 280
 281         keypad->mmio_base = ioremap(res->start, resource_size(res));
 282         if (keypad->mmio_base == NULL) {
 283                 err = -ENXIO;
 284                 goto failed_free_mem;
 285         }
 286
 287         err = ep93xx_keypad_acquire_gpio(pdev);
 288         if (err)
 289                 goto failed_free_io;
 290
 291         keypad->clk = clk_get(&pdev->dev, NULL);
 292         if (IS_ERR(keypad->clk)) {
 293                 err = PTR_ERR(keypad->clk);
 294                 goto failed_free_gpio;
 295         }
 296
 297         input_dev = input_allocate_device();
 298         if (!input_dev) {
 299                 err = -ENOMEM;
 300                 goto failed_put_clk;
 301         }
 302
 303         keypad->input_dev = input_dev;
 304
 305         input_dev->name = pdev->name;
 306         input_dev->id.bustype = BUS_HOST;
 307         input_dev->open = ep93xx_keypad_open;
 308         input_dev->close = ep93xx_keypad_close;
 309         input_dev->dev.parent = &pdev->dev;
 310         input_dev->keycode = keypad->keycodes;
 311         input_dev->keycodesize = sizeof(keypad->keycodes[0]);
 312         input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
 313
 314         input_set_drvdata(input_dev, keypad);
 315
 316         input_dev->evbit[0] = BIT_MASK(EV_KEY);
 317         if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
 318                 input_dev->evbit[0] |= BIT_MASK(EV_REP);
 319
 320         matrix_keypad_build_keymap(keymap_data, 3,
 321                                    input_dev->keycode, input_dev->keybit);
 322         platform_set_drvdata(pdev, keypad);
 323
 324         err = request_irq(keypad->irq, ep93xx_keypad_irq_handler,
 325                           IRQF_DISABLED, pdev->name, keypad);
 326         if (err)
 327                 goto failed_free_dev;
 328
 329         err = input_register_device(input_dev);
 330         if (err)
 331                 goto failed_free_irq;
 332
 333         device_init_wakeup(&pdev->dev, 1);
 334
 335         return 0;
 336
 337 failed_free_irq:
 338         free_irq(keypad->irq, pdev);
 339         platform_set_drvdata(pdev, NULL);
 340 failed_free_dev:
 341         input_free_device(input_dev);
 342 failed_put_clk:
 343         clk_put(keypad->clk);
 344 failed_free_gpio:
 345         ep93xx_keypad_release_gpio(pdev);
 346 failed_free_io:
 347         iounmap(keypad->mmio_base);
 348 failed_free_mem:
 349         release_mem_region(res->start, resource_size(res));
 350 failed_free:
 351         kfree(keypad);
 352         return err;
 353 }
 354
 355 static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
 356 {
 357         struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 358         struct resource *res;
 359
 360         free_irq(keypad->irq, pdev);
 361
 362         platform_set_drvdata(pdev, NULL);
 363
 364         if (keypad->enabled)
 365                 clk_disable(keypad->clk);
 366         clk_put(keypad->clk);
 367
 368         input_unregister_device(keypad->input_dev);
 369
 370         ep93xx_keypad_release_gpio(pdev);
 371
 372         iounmap(keypad->mmio_base);
 373
 374         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 375         release_mem_region(res->start, resource_size(res));
 376
 377         kfree(keypad);
 378
 379         return 0;
 380 }
 381
 382 static struct platform_driver ep93xx_keypad_driver = {
 383         .driver         = {
 384                 .name   = "ep93xx-keypad",
 385                 .owner  = THIS_MODULE,
 386         },
 387         .probe          = ep93xx_keypad_probe,
 388         .remove         = __devexit_p(ep93xx_keypad_remove),
 389         .suspend        = ep93xx_keypad_suspend,
 390         .resume         = ep93xx_keypad_resume,
 391 };
 392
 393 static int __init ep93xx_keypad_init(void)
 394 {
 395         return platform_driver_register(&ep93xx_keypad_driver);
 396 }
 397
 398 static void __exit ep93xx_keypad_exit(void)
 399 {
 400         platform_driver_unregister(&ep93xx_keypad_driver);
 401 }
 402
 403 module_init(ep93xx_keypad_init);
 404 module_exit(ep93xx_keypad_exit);
 405
 406 MODULE_LICENSE("GPL");
 407 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
 408 MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
 409 MODULE_ALIAS("platform:ep93xx-keypad");